An MEKC method for the analysis of goserelin and related substances has been developed using a combination of additives including CTAB, beta-CD, and sodium hexanesulfonate. For this assay, the running buffer (pH and additives) and separation conditions (voltage and temperature) were optimized. The optimized system was the following: 200 mM 6-aminocaproic acid buffer (pH 4.2) supplemented with 175 mM CTAB, 3.0% w/v beta-CD, and 20 mM sodium hexanesulfonate; the voltage was 10 kV in reverse polarity mode, the temperature was 20 degrees C, and UV detection was measured at 220 nm. The method was qualified by evaluating the specificity, precision, linearity, accuracy, LOD, and LOQ. According to validation experiments, the optimized method was specific, accurate, and repeatable and satisfied the requirements for the analysis of goserelin and related substances. Compared with the RP-HPLC method, the MEKC method better solved the problem of overlapping impurity signals, and the migration time required was shorter. This method can be used for quality control and for the analysis of goserelin and its related substances.